/* * RTP parser for VC-2 HQ payload format (draft version 1) - experimental * Copyright (c) 2016 Thomas Volkert <thomas@netzeal.de> * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "libavutil/intreadwrite.h" #include "libavcodec/dirac.h" #include "avio_internal.h" #include "rtpdec_formats.h" #define RTP_VC2HQ_PL_HEADER_SIZE 4 #define DIRAC_DATA_UNIT_HEADER_SIZE 13 #define DIRAC_PIC_NR_SIZE 4 #define DIRAC_RTP_PCODE_HQ_PIC_FRAGMENT 0xEC struct PayloadContext { AVIOContext *buf; uint32_t frame_size; uint32_t frame_nr; uint32_t timestamp; uint32_t last_unit_size; int seen_sequence_header; }; static const uint8_t start_sequence[] = { 'B', 'B', 'C', 'D' }; static void fill_parse_info_header(PayloadContext *pl_ctx, uint8_t *buf, uint8_t parse_code, uint32_t data_unit_size) { memcpy(buf, start_sequence, sizeof(start_sequence)); buf[4] = parse_code; AV_WB32(&buf[5], data_unit_size); AV_WB32(&buf[9], pl_ctx->last_unit_size); pl_ctx->last_unit_size = data_unit_size; } static int vc2hq_handle_sequence_header(PayloadContext *pl_ctx, AVStream *st, AVPacket *pkt, const uint8_t *buf, int len) { int res; uint32_t size = DIRAC_DATA_UNIT_HEADER_SIZE + len; if ((res = av_new_packet(pkt, DIRAC_DATA_UNIT_HEADER_SIZE + len)) < 0) return res; fill_parse_info_header(pl_ctx, pkt->data, 0x00, size); /* payload of seq. header */ memcpy(pkt->data + DIRAC_DATA_UNIT_HEADER_SIZE, buf, len); pkt->stream_index = st->index; pl_ctx->seen_sequence_header = 1; return 0; } static int vc2hq_mark_end_of_sequence(PayloadContext *pl_ctx, AVStream *st, AVPacket *pkt) { int res; uint32_t size = 0; /* create A/V packet */ if ((res = av_new_packet(pkt, DIRAC_DATA_UNIT_HEADER_SIZE)) < 0) return res; fill_parse_info_header(pl_ctx, pkt->data, 0x10, size); pkt->stream_index = st->index; pl_ctx->seen_sequence_header = 0; return 0; } static int vc2hq_handle_frame_fragment(AVFormatContext *ctx, PayloadContext *pl_ctx, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, int flags) { int res; uint32_t pic_nr; uint16_t frag_len; uint16_t no_slices; /* sanity check for size of input packet: 16 bytes header in any case as minimum */ if (len < 16) { av_log(ctx, AV_LOG_ERROR, "Too short RTP/VC2hq packet, got %d bytes\n", len); return AVERROR_INVALIDDATA; } pic_nr = AV_RB32(&buf[4]); frag_len = AV_RB16(&buf[12]); no_slices = AV_RB16(&buf[14]); if (pl_ctx->buf && pl_ctx->frame_nr != pic_nr) { av_log(ctx, AV_LOG_WARNING, "Dropping buffered RTP/VC2hq packet fragments - non-continuous picture numbers\n"); ffio_free_dyn_buf(&pl_ctx->buf); } /* transform parameters? */ if (no_slices == 0) { if (len < frag_len + 16) { av_log(ctx, AV_LOG_ERROR, "Too short RTP/VC2hq packet, got %d bytes\n", len); return AVERROR_INVALIDDATA; } /* start frame buffering with new dynamic buffer */ if (!pl_ctx->buf) { res = avio_open_dyn_buf(&pl_ctx->buf); if (res < 0) return res; /* reserve memory for frame header */ res = avio_seek(pl_ctx->buf, DIRAC_DATA_UNIT_HEADER_SIZE + DIRAC_PIC_NR_SIZE, SEEK_SET); if (res < 0) return res; pl_ctx->frame_nr = pic_nr; pl_ctx->timestamp = *timestamp; pl_ctx->frame_size = DIRAC_DATA_UNIT_HEADER_SIZE + DIRAC_PIC_NR_SIZE; } avio_write(pl_ctx->buf, buf + 16 /* skip pl header */, frag_len); pl_ctx->frame_size += frag_len; return AVERROR(EAGAIN); } else { if (len < frag_len + 20) { av_log(ctx, AV_LOG_ERROR, "Too short RTP/VC2hq packet, got %d bytes\n", len); return AVERROR_INVALIDDATA; } /* transform parameters were missed, no buffer available */ if (!pl_ctx->buf) return AVERROR_INVALIDDATA; avio_write(pl_ctx->buf, buf + 20 /* skip pl header */, frag_len); pl_ctx->frame_size += frag_len; /* RTP marker bit means: last fragment of current frame was received; otherwise, an additional fragment is needed for the current frame */ if (!(flags & RTP_FLAG_MARKER)) return AVERROR(EAGAIN); } /* close frame buffering and create A/V packet */ res = ff_rtp_finalize_packet(pkt, &pl_ctx->buf, st->index); if (res < 0) return res; fill_parse_info_header(pl_ctx, pkt->data, DIRAC_PCODE_PICTURE_HQ, pl_ctx->frame_size); AV_WB32(&pkt->data[13], pl_ctx->frame_nr); pl_ctx->frame_size = 0; return 0; } static int vc2hq_handle_packet(AVFormatContext *ctx, PayloadContext *pl_ctx, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t seq, int flags) { uint8_t parse_code = 0; int res = 0; if (pl_ctx->buf && pl_ctx->timestamp != *timestamp) { av_log(ctx, AV_LOG_WARNING, "Dropping buffered RTP/VC2hq packet fragments - non-continuous timestamps\n"); ffio_free_dyn_buf(&pl_ctx->buf); pl_ctx->frame_size = 0; } /* sanity check for size of input packet: needed header data as minimum */ if (len < RTP_VC2HQ_PL_HEADER_SIZE) { av_log(ctx, AV_LOG_ERROR, "Too short RTP/VC2hq packet, got %d bytes\n", len); return AVERROR_INVALIDDATA; } parse_code = buf[3]; /* wait for next sequence header? */ if (pl_ctx->seen_sequence_header || parse_code == DIRAC_PCODE_SEQ_HEADER) { switch(parse_code) { /* sequence header */ case DIRAC_PCODE_SEQ_HEADER: res = vc2hq_handle_sequence_header(pl_ctx, st, pkt, buf + RTP_VC2HQ_PL_HEADER_SIZE, len - RTP_VC2HQ_PL_HEADER_SIZE); break; /* end of sequence */ case DIRAC_PCODE_END_SEQ: res = vc2hq_mark_end_of_sequence(pl_ctx, st, pkt); break; /* HQ picture fragment */ case DIRAC_RTP_PCODE_HQ_PIC_FRAGMENT: res = vc2hq_handle_frame_fragment(ctx, pl_ctx, st, pkt, timestamp, buf, len, flags); break; } } return res; } RTPDynamicProtocolHandler ff_vc2hq_dynamic_handler = { .enc_name = "VC2", .codec_type = AVMEDIA_TYPE_VIDEO, .codec_id = AV_CODEC_ID_DIRAC, .priv_data_size = sizeof(PayloadContext), .parse_packet = vc2hq_handle_packet };